The present invention relates to a teaching appliances for programmed teaching of the kind which includes a laying out board and answer tablets which are to be laid on the board in a prescribed fashion and wherein means are provided to secure said tablets against lateral displacement.
In a known teaching appliance of the kind described above for programmed teaching, in which two opposing edges of the tablets are of an undulating configuration so that pairs of the tablets will fit together, it is not possible to check the correctness of the answers which have been given until after a certain stage has been reached. This only becomes possible when a tablet being laid has to be laid down abutting a tablet already down. If when this is done it is found that the undulations of the tablet being laid down will not fit into those of the tablet already down, the wrong answer has been given to the question corresponding either to the tablet already laid or to the tablet about to be laid. As a rule, the question corresponding to the tablet already laid has then to be answered again and only then can that corresponding to the other tablet be answered. It is true that this is a sure way of showing up a wrongly answered question, but on the other hand the questions concerned have first to be answered correctly, that is to say the tablets have to be laid down correctly, before other tablets can be laid down abutting them. Admittedly, all the questions will eventually be correctly answered in this way once all the tablets have been laid down, but because of incorrectly answered questions it may take a very long time to get all the tablets laid down and as a result children may lose interest in answering all the questions. Also when all the questions have been answered, there is no way of finding out how many questions were answered incorrectly and which these were.
It is an object of the invention to provide a simply constructed teaching appliance with which the questions already answered can be checked at any time and it can at once be determined, if desired, how many questions have been wrongly answered and which these are, and which is almost completely proof against cheating. The intention is also to provide a relatively large number of possible codings with a comparatively small number of tablets.